This invention relates to a machine for hollowing vegetables, fruits or parts thereof having at their base a central portion to be separated along a hemspherical or ogival surface from the surrounding portion.
Machines for hollowing such products as vegetables and fruits, where the product is placed with the stalk cut off during harvest turned upward in recesses or holders, are known. These recesses are moved discontinuously along a circular or straight path, while a circular blade of invariable diameter makes a cylindrical hollow in the product, or the products are placed with the stalk portions turned downward in recesses, while a bent knife of variable diameter makes a convex cut for cutting out the central portion of the vegetable or fruit.
An example of a previously known machine is given in U.S. Pat. No. 2,252,951. According to this document tomatoes are hollowed from above by a bent knife. Other examples of known machines are given in the French Patent No. No. 1,457,722 and the Swedish Patent No. 771662-1. The French patent relates to separation of chosen parts of an artichoke, where a bent knife works from below with a variable cutting diameter. The Swedish patent relates to a machine for paring vegetables and fruits, especially cauliflower, and here as well a bent knife works from below with a variable diameter.
These known machines with bent knives are the most optimal, since the diameter of the cut out central portion is adapted to the diameter of the product and the convex form of the cut out central portion corresponds to the form of that part of the product that one wishes to separate before further processing the product.
The disadvantages of the known devices are nevertheless that the cut out central portion leaves the machine together with the usable part of the product and it is therefore necessary to manually separate the central portion from the usable part of the product on a sorting band and it is not possible to vary the form, i.e., the ratio between the diameter and the height, of the cut out portion.